AT&T and LG have just made the Nitro HD official and it's the Optimus LTE for the US of A. Yes, it packs a 4.5-inch 720p display, a dual-core 1.5GHz CPU, 4GB of storage along with a 16GB microSD card, and Android "Gingerbread". The smartphone can be yours starting this Sunday, December 4th, for $249.99 on a 2-year contract.